Haemoglobinometry on automated haematology analysers

Area of Science:

• Clinical Chemistry
• Hematology Automation

Background:

• The cyanmethaemoglobin (HiCN) method is standard for haemoglobin determination.
• Automated analysers have limited reaction times, potentially affecting HiCN accuracy.
• Variations in haemoglobin derivatives can impact results in automated systems.

Purpose of the Study:

• To evaluate the haemoglobin determination methods used in automated blood analysers.
• To investigate the suitability of alternative haemoglobin derivatives for automated analysis.
• To assess the impact of reagent composition on analyser performance.

Main Methods:

• Comparative analysis of haemoglobin determination in Ortho ELT800 and Coulter S Plus III analysers.
• Investigation of reaction kinetics for cyanmethaemoglobin (HiCN) formation.
• Assessment of haemoglobin derivative stability and conversion times.

Main Results:

• The Ortho ELT800 requires over 25 seconds for HiCN conversion.
• Automated analysers likely use denatured globin haemichrome, not HiCN, as the end product.
• Haemichrome formation is rapid and consistent across various haemoglobin derivatives, including HbCO.
• The Coulter S Plus III produces an unstable haemoglobin derivative in its combined white cell and haemoglobin analysis channel.

Conclusions:

• Denatured globin haemichrome is a suitable alternative for automated haemoglobin analysis due to its rapid conversion.
• Separate analysis channels with optimized reagents are recommended for white cell and haemoglobin determination.
• Manufacturers should provide accurate information on the chemistry and reagents used in their haemoglobin analysers.